Modular arrangements of circuit interrupters like circuit breakers for use in commercial and industrial power systems have previously been adapted for attachment to the busbars in panelboards, switchgear, and other distribution boards. These modular arrangements serve to establish electrical connections to service lines and allow for outgoing connections to the branch circuits.
Some of the well known distribution boards provide modules or cells which accept circuit breakers having a width of about 11/2 inch. Attempting to assemble and insert circuit breakers having a width other than 11/2 inch into a module or cell of this type could result in serious misalignment of the electrical and mechanical connections between the circuit breaker and the busbar.
The technological advances of the art have enabled smaller, more powerful circuit breakers to be developed. While these new circuit breakers have been able to put more power in less space, many end users of distribution systems currently have cells and/or busbars which cannot accommodate the dimensions of the smaller new devices. To avoid the expense of replacing these distribution systems, there is a need to adapt the different dimensional size and electrical contacts of the new circuit breakers with existing cells and/or busbar contacts.
Another problem encountered by busbars and the modular or cell arrangement of the distribution boards lies in making the connection between the circuit breaker and the busbar. When resilient contact jaws are used by the circuit breaker to connect to the busbars, the force required to make the physical connection to the busbar is substantial. Making this connection becomes even more difficult when the contact jaws do not precisely align with the busbars. Additional force may be needed to compensate for the misalignment.
There is a need for mounting an assembly of circuit breakers to a module or cell of a distribution board where the module or cell was originally made to accommodate circuit breakers of a different, usually larger, physical size. Additionally, there is a need for a new and improved circuit breaker assembly which provides a movable contact jaw to ensure accurate alignment of the circuit breaker and the busbar in the distribution board.